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प्रश्न
Sulphide ores : Roasting : : Carbonate ores : _______
उत्तर
Sulphide ores : Roasting : : Carbonate ores : Calcination
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संबंधित प्रश्न
Give reasons.
Aluminium is a highly reactive metal, yet it is used to make utensils for cooking.
How many carats is pure gold? Why is pure gold not suitable for making ornaments?
Give the name and chemical formula of one ore of copper.
Describe with one example, how moderately reactive metals (which are in the middle of reactivity series) are extracted.
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Name three other metals which are extracted in a manner similar to sodium.
Explain how, mercury is extracted from its sulphide ore (cinnabar). Give equations of the reactions involved.
Which of the following reactants are used to carry out the thermite reaction required for welding the broken railway tracks?
(a) Al2O3 + Fe
(b) MnO2 + Al
(c) Fe2O3 + Al
(d) Cu2O + Fe
Which of the following metals can be obtained from haematite ore?
(a) copper
(b) sodium
(c) zinc
(d) iron
A sulphide ore is converted into metal oxide by the process of:
(a) carbonation
(b) roasting
(c) calcination
(d) anodising
A black metal oxide XO2 is used as a catalyst in the preparation of oxygen gas from potassium chlorate. The oxide XO2 is also used in ordinary dry cells. The metal oxide XO2 cannot be reduced satisfactorily with carbon to form metal X.
(a) Name the metal X.
(b) Name the metal oxide XO2.
(c) Which reducing agent can be used to reduce XO2 to obtain metal X?
(d) Name another metal which can also be extracted by the reduction of its oxide with the above reducing agent.
Metals X and Y can be recovered from the anode mud left behind after the electrolytic refining of copper metal. The coins made of metal X look new even after several years of use but the coins made of metal Y lose their shine gradually and get blackened soon. When metal X is alloyed with a small amount of metal Y, it becomes hard and hence suitable for making ornaments. What are metals X and Y? Also state the colour of metal X.
What is passive iron?
Write equations for each of the above metal which reacts with water.
Which one of the following is not true of metal :
Metals form non-polar covalent compounds
How is the method of extraction of metals high up in the reactivity series different from that for metals in the middle? Why can the same process not be applied for them? Name the process used for the extraction of these metals.
Aluminium oxide is _______ oxide.
Write the name.
The process of extraction of aluminium from alumina-
Write the molecular formulae of the following compound.
Cryolite
Which of the following metals exist in their native state in nature?
- Cu
- Au
- Zn
- Ag
